KR20110101894A - Liquid crsytal display - Google Patents

Abstract

The liquid crystal display according to the exemplary embodiment of the present invention may include a first substrate and a second substrate facing each other, a plurality of signal lines disposed on the first substrate, and a plurality of signal lines connected to the plurality of signal lines and separated from each other. A liquid crystal layer including a first pixel electrode and a second pixel electrode, and a liquid crystal layer interposed between the first substrate and the second substrate and including liquid crystal molecules, and disposed in a region occupied by the first subpixel electrode. The voltage charged at is lower than the voltage charged at the liquid crystal layer disposed in the area occupied by the second subpixel electrode, and the area occupied by a portion of the first subpixel electrode and the second subpixel electrode is a first color. , And an area occupied by the remaining part of the first subpixel electrode displays a second color.

Description

Liquid crystal display {LIQUID CRSYTAL DISPLAY}

The present invention relates to a liquid crystal display device.

The liquid crystal display is one of the flat panel display devices most widely used. The liquid crystal display includes two display panels on which field generating electrodes, such as a pixel electrode and a common electrode, are formed, and a liquid crystal layer interposed therebetween. Is applied to generate an electric field in the liquid crystal layer, thereby determining the orientation of the liquid crystal molecules of the liquid crystal layer and controlling the polarization of incident light to display an image.

In order to improve the display quality of the liquid crystal display, it is necessary to implement a liquid crystal display capable of having a high contrast ratio, an excellent wide viewing angle, and a fast response speed.

In addition, it is necessary to implement a liquid crystal display device having a high light transmittance. In order to increase the light transmittance of the liquid crystal display, a method of implementing each pixel with four pixels, such as three primary colors such as red, green, and blue, and white, has been developed. However, when one of the three primary colors or white is respectively displayed in one pixel area, color reproducibility at low gray levels may be lowered.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a liquid crystal display device capable of increasing color reproducibility in low grayscale and increasing luminance in high grayscale.

The liquid crystal display according to the exemplary embodiment of the present invention includes a first substrate and a second substrate facing each other, a plurality of signal lines disposed on the first substrate, and a plurality of signal lines connected to and separated from each other. A first pixel electrode and a second pixel electrode, the first pixel electrode and the second pixel electrode includes a plurality of branch electrodes, the branch electrode of the first pixel electrode and the branch electrode of the second pixel electrode The first pixel electrode and the second pixel electrode are alternately disposed, and the first region and the neighboring region between the branch electrode of the neighboring first pixel electrode and the branch electrode of the second pixel electrode are a first distance. And a second area having a second distance smaller than the first distance between the branch electrode of the first pixel electrode and the branch electrode of the second pixel electrode. The second area displays a first color, and the remaining part of the first area displays a second color.

The first color may be any one of the primary colors, and the second color may be white or yellow.

A color filter may be disposed in an area displaying the first color, and a color filter may be removed in an area displaying the second color.

The color filter may be disposed on the first substrate.

The color filter may be disposed between the signal line and the pixel electrode, and a transparent organic insulating layer may be disposed in a region displaying the second color.

The color filter may be disposed on the second substrate.

An area displaying the second color may be within 20% of the total area occupied by the first pixel electrode and the second pixel electrode.

An area of the area displaying the second color of the first area may be less than or equal to 1/2 of an area of the area displaying the first color of the first area.

The liquid crystal display further comprises a liquid crystal layer disposed between the first substrate and the second substrate, wherein the liquid crystal molecules of the liquid crystal layer have long axes of the first substrate and the second substrate in the absence of an electric field. It may be perpendicular to the surface of.

The first region further includes a third region in which a distance between the branch electrodes of the first pixel electrode and the branch electrodes of the second pixel electrode, which are adjacent to each other, is a third distance greater than the first distance, and the first region An area displaying the second color may be the third area.

An area of the third region is equal to or smaller than an area of the second region, and a distance between the branch electrode of the first pixel electrode and the branch electrode of the second pixel electrode adjacent to each other among the first regions is equal to the first region. The area of the distance area may be at least three times the area of the third area.

According to another exemplary embodiment, a liquid crystal display device includes a first substrate and a second substrate facing each other, a plurality of signal lines disposed on the first substrate, and a plurality of signal lines connected to the plurality of signal lines and separated from each other. A pixel electrode including a first subpixel electrode and a second subpixel electrode, and a liquid crystal layer interposed between the first substrate and the second substrate, the liquid crystal layer including liquid crystal molecules, and occupied by the first subpixel electrode. The voltage charged in the liquid crystal layer disposed in the region is lower than the voltage charged in the liquid crystal layer disposed in the region occupied by the second subpixel electrode, and a part of the first subpixel electrode and the second subpixel electrode The area occupied displays the first color, and the area occupied by the remaining part of the first subpixel electrode displays the second color.

An area displaying the second color may be within 20% of the total area occupied by the first pixel electrode and the second pixel electrode.

An area of the area displaying the second color of the area occupied by the first pixel electrode may be about 1/2 or less of an area of the area displaying the first color of the area occupied by the first pixel electrode.

According to an exemplary embodiment of the present invention, the color reproducibility can be maintained high without reducing the transmittance or the resolution of the liquid crystal display, and in particular, the color reproducibility in low gradations and the brightness in high gradations can be increased.

1A and 1B, and FIGS. 2 and 3 are layout views schematically illustrating a structure of a liquid crystal display according to an exemplary embodiment of the present invention.
4 is an equivalent circuit diagram illustrating one pixel together with the structure of a liquid crystal display according to an exemplary embodiment of the present invention.
5 is a schematic cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.
6 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention.
FIG. 7 is a cross-sectional view of the liquid crystal display of FIG. 6 taken along the line VII-VII. FIG.
8 is an equivalent circuit diagram illustrating one pixel together with the structure of a liquid crystal display according to another exemplary embodiment of the present invention.
9 is a layout view of a liquid crystal display according to another exemplary embodiment of the present invention.
FIG. 10 is a cross-sectional view of the liquid crystal display of FIG. 9 taken along the line IX-IX. FIG.
11 is a layout view of a liquid crystal display according to another exemplary embodiment of the present invention.
FIG. 12 is a cross-sectional view of the liquid crystal display illustrated in FIG. 11 taken along the line XII-XII.
13 is a graph showing a voltage-transmittance curve according to an experimental example of the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a part of a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the other part being "right over" but also another part in the middle. On the contrary, when a part is "just above" another part, there is no other part in the middle.

A liquid crystal display according to an exemplary embodiment of the present invention will now be briefly described with reference to the drawings.

1A and 1B, and FIGS. 2 and 3 are layout views schematically illustrating a structure of a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 1A, a liquid crystal display according to an exemplary embodiment of the present invention includes a first pixel PXa, a second pixel PXb, and a third pixel PXc. The first pixel PXa, the second pixel PXb, and the third pixel PXc each include a high pixel area PX_high and a low pixel area PX_low. Under the same conditions, the intensity of the electric field applied to the liquid crystal layer disposed in the high pixel region PX_high is greater than the intensity of the electric field applied to the liquid crystal layer disposed in the low pixel region PX_low.

A portion of the high pixel area PX_high and the low pixel area PX_low of the first pixel PXa display the first color Ca, and the high pixel area PX_high and the low pixel area of the second pixel PXb. A portion of the PX_low displays the second color Cb, and a portion of the high pixel area PX_high and the low pixel area PX_low of the third pixel PXc display the third color Cc. The remaining part of the low pixel area PX_low of the first pixel PXa, the remaining part of the low pixel area PX_low of the second pixel PXb, and the remaining part of the low pixel area PX_low of the third pixel PXc. Denotes the fourth color Cd. Here, the first color Ca, the second color Cb, and the third color Cc may be any one of red, blue, and green, and the fourth color Cd may be white or yellow. The color filter may be disposed in an area displaying the first color Ca, the second color Cb, and the third color Cc. In addition, a color filter may be removed from a region displaying the fourth color Cd, and a white color filter or a yellow color filter may be disposed. The area displaying the fourth color Cd is disposed at an edge of the low pixel area PX_low displaying the first color Ca, the second color Cb, and the third color Cc. At this time, the area of the region displaying the fourth color Cd is preferably within 20% of the area of each pixel region PXa, PXb, or PXc.

Referring to FIG. 1B, the liquid crystal display according to the present embodiment is similar to the liquid crystal display according to the embodiment shown in FIG. 1A.

Referring to FIG. 1B, the liquid crystal display according to the exemplary embodiment of the present invention includes a first pixel PXa, a second pixel PXb, and a third pixel PXc. Each of the first pixel PXa, the second pixel PXb, and the third pixel PXc includes a high pixel area PX_high, an intermediate pixel area PX_middle, and a low pixel area PX_low. Under the same conditions, the intensity of the electric field applied to the liquid crystal layer disposed in the high pixel region PX_high is relatively largest, and the intensity of the electric field applied to the liquid crystal layer disposed in the low pixel region PX_low is relatively small. The electric field applied to the liquid crystal layer disposed in the middle pixel region PX_middle is greater than the electric field applied to the liquid crystal layer in the low pixel region PX_low and the electric field applied to the liquid crystal layer of the high pixel region PX_high. Is less than a century.

The high pixel area PX_high and the middle pixel area PX_middle of the first pixel PXa display the first color Ca, and the high pixel area PX_high and the intermediate pixel area PX_middle of the second pixel PXb. ) Displays the second color Cb, and the high pixel area PX_high and the middle pixel area PX_middle of the third pixel PXc display the third color Cc. The low pixel area PX_low of the first pixel PXa, the low pixel area PX_low of the second pixel PXb, and the low pixel area PX_low of the third pixel PXc each have a fourth color Cd. Display. Here, the first color Ca, the second color Cb, and the third color Cc may be any one of red, blue, and green, and the fourth color Cd may be white or yellow. The color filter may be disposed in an area displaying the first color Ca, the second color Cb, and the third color Cc. In addition, a color filter may be removed from a region displaying the fourth color Cd, and a white color filter or a yellow color filter may be disposed. At this time, the area of the area displaying the fourth color Cd is preferably within 20% of the area of each pixel area PXa, PXb, or PXc.

Referring to FIG. 2, the liquid crystal display according to the present embodiment is similar to the liquid crystal display according to the embodiment shown in FIG. 1.

The liquid crystal display according to the present exemplary embodiment includes a first pixel PXa, a second pixel PXb, and a third pixel PXc, and includes a first pixel PXa, a second pixel PXb, and a third pixel. PXc includes a high pixel area PX_high and a low pixel area PX_low, respectively.

A portion of the high pixel area PX_high and the low pixel area PX_low of the first pixel PXa display the first color Ca, and the high pixel area PX_high and the low pixel area of the second pixel PXb. A portion of the PX_low displays the second color Cb, and a portion of the high pixel area PX_high and the low pixel area PX_low of the third pixel PXc display the third color Cc. The remaining part of the low pixel area PX_low of the first pixel PXa, the remaining part of the low pixel area PX_low of the second pixel PXb, and the remaining part of the low pixel area PX_low of the third pixel PXc. Denotes the fourth color Cd. At this time, the area of the area displaying the fourth color Cd is preferably within 20% of the area of each pixel area PXa, PXb, or PXc.

However, the arrangement of the high pixel area PX_high and the low pixel area PX_low of each pixel PXa, PXb, and PXc is different from that of the liquid crystal display according to the exemplary embodiment shown in FIG. 1. The high pixel area PX_high and the low pixel area PX_low of the liquid crystal display according to the present exemplary embodiment are disposed above and below the pixel area, and have a first color (a periphery around the area displaying the fourth color Cd). The area | region which displays Ca), 2nd color Cb, and 3rd color Cc is arrange | positioned.

Next, referring to FIG. 3, the liquid crystal display according to the present embodiment is similar to the liquid crystal display according to the embodiment shown in FIG. 1.

The liquid crystal display according to the present exemplary embodiment includes a first pixel PXa, a second pixel PXb, and a third pixel PXc, and includes a first pixel PXa, a second pixel PXb, and a third pixel. PXc includes a high pixel area PX_high and a low pixel area PX_low, respectively.

A portion of the high pixel area PX_high and the low pixel area PX_low of the first pixel PXa display the first color Ca, and the high pixel area PX_high and the low pixel area of the second pixel PXb. A portion of the PX_low displays the second color Cb, and a portion of the high pixel area PX_high and the low pixel area PX_low of the third pixel PXc display the third color Cc. The remaining part of the low pixel area PX_low of the first pixel PXa, the remaining part of the low pixel area PX_low of the second pixel PXb, and the remaining part of the low pixel area PX_low of the third pixel PXc. Denotes the fourth color Cd. At this time, the area of the area displaying the fourth color Cd is preferably within 20% of the area of each pixel area PXa, PXb, or PXc.

However, the arrangement of the high pixel area PX_high and the low pixel area PX_low of each pixel PXa, PXb, and PXc is different from that of the liquid crystal display according to the exemplary embodiment shown in FIG. 1. The high pixel area PX_high of the liquid crystal display according to the present exemplary embodiment is surrounded by the low pixel area PX_low. The area displaying the fourth color Cd is disposed at an edge of the low pixel area PX_low displaying the first color Ca, the second color Cb, and the third color Cc.

Next, the liquid crystal display according to the exemplary embodiment of the present invention will be described in detail with reference to FIGS. 4 to 7. 4 is an equivalent circuit diagram showing one pixel together with the structure of a liquid crystal display according to an embodiment of the present invention, FIG. 5 is a simplified cross-sectional view of the liquid crystal display according to an embodiment of the present invention, and FIG. FIG. 7 is a layout view of a liquid crystal display according to an exemplary embodiment, and FIG. 7 is a cross-sectional view of the liquid crystal display of FIG. 6 taken along the line VII-VII.

Referring to FIG. 4, in the liquid crystal display according to the exemplary embodiment, the liquid crystal layer 3 disposed between the lower panel 100 and the upper panel 200 and the two display panels 100 and 200 facing each other. It includes. Each pixel PX includes a switching element (not shown) connected to a signal line (not shown), a liquid crystal capacitor Clc, and first and second storage capacitors Csta and Qstb connected thereto. ). The first and second holding capacitors Csta and Cstb may be omitted as necessary.

The liquid crystal capacitor Clc has the first pixel electrode PEa and the second pixel electrode PEb of the lower panel 100 as two terminals, and the liquid crystal layer 3 between the first and second pixel electrodes PEa and PEb. ) Functions as a dielectric.

The liquid crystal layer 3 has dielectric anisotropy, and the liquid crystal molecules of the liquid crystal layer 3 may be aligned such that their major axes are perpendicular to the surfaces of the two display panels in the absence of an electric field.

In the first and second storage capacitors Csta and Cstb, which serve as an auxiliary role of the liquid crystal capacitor Clc, a separate electrode (not shown) provided in the lower display panel 100 includes the first and second pixel electrodes PEa. , PEb) may be formed to overlap each other with an insulator interposed therebetween.

Meanwhile, in order to implement color display, each pixel PX uniquely displays one or more of the primary colors so that a desired color is recognized by the spatial and temporal sum of these primary colors. Examples of the primary colors include three primary colors such as red, green, and blue, and white or yellow.

An example of a driving method of a liquid crystal display according to an exemplary embodiment of the present invention will be described with reference to FIG. 5.

4 and 5, when different voltages are applied to the first pixel electrode PEa and the second pixel electrode PEb, the first and second pixel electrodes PEa and PEb are applied to the first and second pixel electrodes PEa and PEb. The difference between the two different voltages is represented as the charging voltage of the liquid crystal capacitor Clc, that is, the pixel voltage. When a potential difference occurs between both ends of the liquid crystal capacitor Clc, as shown in FIG. 5, an electric field parallel to the surfaces of the display panels 100 and 200 may be formed between the first pixel electrode PEa and the second pixel electrode PEb. (3) is generated. When the liquid crystal molecules 31 have positive dielectric anisotropy, the liquid crystal molecules 31 are inclined such that their major axis is parallel to the direction of the electric field, and the degree of inclination depends on the magnitude of the pixel voltage. In addition, the degree of change in polarization of light passing through the liquid crystal layer 3 varies according to the degree of inclination of the liquid crystal molecules 31. This change in polarization is represented by a change in the transmittance of light by the polarizer, whereby the pixel PX displays a desired luminance.

An example of the liquid crystal display described with reference to FIGS. 4 and 5 will now be described in detail with reference to FIGS. 6 and 7.

6 and 7, a liquid crystal display according to an exemplary embodiment of the present invention includes a lower panel 100 and an upper panel 200 facing each other, and a liquid crystal layer interposed between the two display panels 100 and 200. It includes (3).

First, the lower panel 100 will be described.

A plurality of gate conductive layers including a plurality of gate lines 121, a plurality of storage electrode lines 131a, and a plurality of power supplying lines 131b on the insulating substrate 110. A sieve is formed.

The gate line 121 transmits a gate signal and mainly extends in a horizontal direction, and each gate line 121 includes a plurality of pairs of first and second gate electrodes 124a and 124b protruding upward. do.

The storage electrode line 131 receives a predetermined voltage and mainly extends in the horizontal direction. Each storage electrode line 131 is located between two adjacent gate lines 121 and is closer to the gate line 121 positioned below.

The gate conductors 121, 131a, and 131b may have a single layer or multiple layer structure.

A gate insulating layer 140 made of silicon nitride (SiNx) or silicon oxide (SiOx) is formed on the gate conductors 121, 131a, and 131b.

A plurality of pairs of first and second island-like semiconductors 154a and 154b made of hydrogenated amorphous or polycrystalline silicon are formed on the gate insulating layer 140. The first and second semiconductors 154a and 154b are positioned on the first and second gate electrodes 124a and 124b, respectively.

A pair of island-like ohmic contacts 163a and 165a are formed on each of the first semiconductors 154a, and a pair of island-like ohmic contacts (not shown) are formed on each of the second semiconductors 154b. ) Is formed. The ohmic contacts 163a and 165a may be made of a material such as n + hydrogenated amorphous silicon in which n-type impurities such as phosphorus are heavily doped, or may be made of silicide.

On the ohmic contacts 163a and 165a and the gate insulating layer 140, a data line 171 including a first source electrode 173a and first and second drain electrodes. A data conductor including 175a and 175b and second source electrode 173b is formed.

The data line 171 transmits a data signal and mainly extends in a vertical direction to cross the gate line 121, the storage electrode line 131a, and the power line 131b.

Each of the first drain electrode 175a and the second drain electrode 175b includes a rod-shaped one end portion and a wide first area 177a and second area 177b.

The rod-shaped one end portions of the first drain electrode 175a and the second drain electrode 175a / 175b may be formed around the first gate electrode 124a and the second gate electrode 124b and may be formed of the first source electrode 173a. And partially surrounded by the bent first source electrode 173a and the second source electrode 173b facing the second source electrode 173b.

One end portion 176 of the second source electrode 173b is physically and electrically connected to the power supply line 131b through a contact hole 141 formed in the gate line 140 to receive a voltage having a predetermined magnitude. .

The data conductors 171, 173b, 175a, and 175b may have a single layer or multiple layer structure.

The ohmic contacts 163a and 165a exist only between the semiconductors 154a and 154b below and the data conductors 171a, 171b, 175a and 175b thereon, and lower the contact resistance therebetween. The semiconductors 154a and 154b have portions exposed between the source electrodes 173a and 173b and the drain electrodes 175a and 175b and not covered by the data conductors 171a, 171b, 175a and 175b.

The lower passivation layer 180p is formed on the data conductors 171a, 171b, 175a, and 175b and the exposed portions of the semiconductors 154a and 154b.

The lower passivation layer 180p may be made of an inorganic insulator such as silicon nitride or silicon oxide, and may prevent the components of the color filter 230 formed thereon from being diffused into the underlying thin film transistor.

A plurality of color filters 230 are formed on the lower passivation layer 180p. The color filter 230 may display one of primary colors such as three primary colors of red, green, and blue, and may be formed of an organic material including a pigment displaying one of the three primary colors.

The color filter 230 is removed in a part of the pixel area. The region where the color filter 230 is removed displays white or yellow color.

In the illustrated embodiment, the color filter 230 is formed on the lower panel 100, but in another embodiment, the color filter 230 may be formed on the upper panel 200.

An upper passivation layer 180q is formed on the lower passivation layer 180p and the plurality of color filters 230. The upper passivation layer 180q may be formed of an organic insulating layer, and may be formed of an organic material having photosensitivity. In addition, the upper passivation layer 180q may be formed to have a thickness of 1.0 μm or more to reduce the coupling phenomenon between the pixel electrode 191 and the data line 171 and to planarize the substrate. The upper passivation layer 180q prevents the color filter 230 from floating and suppresses contamination of the liquid crystal layer 3 by organic substances such as a solvent flowing from the color filter 230, resulting in afterimages that may occur when driving the screen. To prevent such defects.

In the upper passivation layer 180q and the lower passivation layer 180p, a plurality of contact holes exposing the first extension 177a of the first drain electrode 175a and the second extension 177b of the second drain electrode 175b ( 185a and 185b are formed.

On the upper passivation layer 180q, a plurality of pairs of first and second pixel electrodes made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) or a reflective metal such as aluminum, silver, chromium or an alloy thereof ( A plurality of pixel electrodes 191 including pixel electrodes 191a and 191b are formed.

The overall outline of one pixel electrode 191 is a quadrangle and the first and second pixel electrodes 191a and 191b include a plurality of branches. Branch portions of the first and second pixel electrodes 191a and 191b are alternately arranged to be interlocked with each other at regular intervals to form a comb-tooth pattern. An angle formed of the branch part with the gate line 121 or the virtual horizontal center line (not shown) may be approximately 45 degrees.

The pixel area is divided into two upper and lower sub-areas bordering on a virtual horizontal center line. Each subregion includes a first region HA having a relatively narrowest distance d1 between the first pixel electrode 191a and the second pixel electrode 191b, the first pixel electrode 191a and the second pixel electrode ( A second region MA having a distance d2 between 191b wider than a first region HA, and a largest spaced distance d3 between the first pixel electrode 191a and the second pixel electrode 191b; It includes three regions LA. That is, the distance d2 between the first pixel electrode 191a and the second pixel electrode 191b in the second area MA is equal to the first pixel electrode 191a and the second pixel in the first area HA. It is wider than the interval d1 between the electrodes 191b and smaller than the interval d3 between the first pixel electrode 191a and the second pixel electrode 191b in the third region LA. For example, the distance d1 between the first pixel electrode 191a and the second pixel electrode 191b of the first area HA may be about 8.5 μm to 9.5 μm, more specifically about 9 μm. The interval d2 between the first pixel electrode 191a and the second pixel electrode 191b of the second area MA may be about 14.5 μm to 15.5 μm, more specifically about 15 μm, and the third area An interval d3 between the first pixel electrode 191a and the second pixel electrode 191b of the LA may be about 18.5 μm to 19.5 μm, more specifically about 19 μm.

The color filter 230 described above is disposed in the first area HA and the second area MA, and is removed in the third area LA. In this case, the area of the third area LA from which the color filter 230 is removed is preferably within 20% of the pixel area. In addition, the area of the third area LA from which the color filter 230 is removed is preferably equal to or smaller than the area of the first area HA, and is equal to or smaller than 1/3 of the area of the second area MA. It is preferable.

The first and second pixel electrodes 191a and 191b are physically and electrically connected to the first and second drain electrodes 175a and 175b through the contact holes 185a and 185b and are connected to the first and second drain electrodes. Voltage is applied from 175a / 175b. The first and second subpixel electrodes 191a and 191b form a liquid crystal capacitor Clc with a portion of the liquid crystal layer 3 therebetween.

The first pixel electrode 191a receives a data voltage from the first drain electrode 175a, and the second pixel electrode 191b receives a voltage having a constant magnitude flowing from the second drain electrode 175b to the power line 131b. Is authorized. In this case, the difference between the voltages applied to the first pixel electrode 191a and the second pixel electrode 191b is a voltage corresponding to the luminance of the pixel PX, and the polarities of the reference voltages may be opposite to each other. .

When voltages are respectively applied to the first pixel electrode 191a and the second pixel electrode 191b, the first pixel electrode may be formed due to a difference in voltage applied to the first pixel electrode 191a and the second pixel electrode 191b. An electric field is applied to the liquid crystal molecules 31 between 191a and the second pixel electrode 191b. In this case, the intensity of the electric field applied to the liquid crystal molecules 31 disposed in the first region HA having the narrowest interval between the first pixel electrode 191a and the second pixel electrode 191b is greatest, and the first The intensity of the electric field applied to the liquid crystal molecules 31 disposed in the third region LA having the narrowest gap between the pixel electrode 191a and the second pixel electrode 191b is smallest, and the second region MA is small. The intensity of the electric field applied to the liquid crystal molecules 31 disposed in the region has a value between the intensity of the electric field applied to the liquid crystal molecules 31 disposed in the first region HA and the third region LA. .

As such, by dividing one pixel PX region into three regions HA, MA, and LA having different intensities of electric fields applied to the liquid crystal layer 3, the visibility in the left and right viewing angle directions is changed by changing the alignment directions of the liquid crystal molecules. Can be improved.

Next, the upper panel 200 will be described.

A light blocking member 220 is formed on an insulating substrate 210 made of transparent glass, plastic, or the like. The light blocking member 220 prevents light leakage between the pixel electrodes 191 and defines an opening area facing the pixel electrode 191. The light blocking member 220 may be disposed on the lower panel 100.

An overcoat 250 is formed on the substrate 210 and the light blocking member 220. The overcoat 250 may be made of an (organic) insulator and prevents the pigment component of the light blocking member 220 from being exposed to the liquid crystal layer 3 and provides a flat surface. The overcoat 250 may be omitted.

An alignment layer (not shown) is coated on inner surfaces of the lower panel 100 and the upper panel 200, and may be a vertical alignment layer.

Polarizers (not shown) may be provided on the outer surfaces of the display panels 100 and 200.

The liquid crystal layer 3 between the lower panel 100 and the upper panel 200 includes liquid crystal molecules 31 having positive dielectric anisotropy, and the liquid crystal molecules 31 have two long axes in the absence of an electric field. The display panels 100 and 200 may be oriented perpendicular to the surfaces of the display panels 100 and 200.

When two voltages having different polarities are applied to the first and second pixel electrodes 191a and 191b, an electric field that is substantially horizontal to the surfaces of the display panels 100 and 200 is generated. Then, the liquid crystal molecules of the liquid crystal layer 3 which are initially oriented perpendicular to the surfaces of the display panels 100 and 200 are inclined in a direction horizontal to the direction of the electric field in response to the electric field, and the liquid crystal molecules are tilted. The degree of change in polarization of incident light in the liquid crystal layer 3 varies depending on the degree. This change in polarization is represented by a change in transmittance by the polarizer, through which the liquid crystal display displays an image.

Using the vertically aligned liquid crystal molecules 31 may increase the contrast ratio of the liquid crystal display and implement a wide viewing angle. In addition, by applying two voltages having different polarities with respect to the reference voltage to one pixel PX, the driving voltage can be increased and the response speed can be increased. In addition, the effect of kickback voltage is eliminated to prevent the flicker phenomenon.

Furthermore, when the liquid crystal molecules 31 vertically aligned with respect to the display panels 100 and 200 are used, the contrast ratio of the liquid crystal display device can be increased and a wide viewing angle can be realized. In addition, the liquid crystal molecule 31 having positive dielectric anisotropy has a high dielectric constant anisotropy and a low rotational viscosity compared to the liquid crystal molecule having negative dielectric anisotropy, thereby obtaining a fast response speed.

In addition, as described above, at least two regions having different intensity of electric field applied to one pixel PX of the liquid crystal display according to the exemplary embodiment of the present invention to the liquid crystal layer 3, more specifically, three regions HA and MA. , LA), it is possible to improve the visibility in the left and right viewing angle direction by changing the alignment direction of the liquid crystal molecules.

In the illustrated embodiment, one pixel PX of the liquid crystal display device is divided into three regions HA, MA, and LA having different intensities, but is applied to the liquid crystal layer 3. It can also be divided into two areas, one with a large electric field and one with a small electric field. In this case, the color filter 230 is disposed in a region where the intensity of the electric field applied to the liquid crystal layer 3 is large, and is disposed only in a part of the region where the intensity of the electric field applied to the liquid crystal layer 3 is small, In some cases it may be removed. In this case, the area of the area where the color filter is not disposed among the areas with small electric field intensity within one pixel area is less than 20% of the total area of the pixel area, and the area of the area where the color filter is disposed among the area with small electric field intensity is present. It is preferable that it is 1/2 or less.

In addition, the color filter 230 is disposed only in the first region HA and the second region MA, in which the electric field applied to the liquid crystal layer 3 has a relatively high intensity, and the electric field applied to the liquid crystal layer 3. This intensity is removed in the third region LA where the intensity is relatively small. In the third region LA having the smallest electric field applied to the liquid crystal layer 3, light is not transmitted at low gradations, but only at high gradations. Therefore, in the case of the liquid crystal display according to the present exemplary embodiment, in the low gradation, light passes through only the first region HA and the second region MA, so that light passing through the color filter 230 is displayed, and thus the color is displayed. Reproducibility is increased, and light is transmitted through all of the first region HA, the second region MA, and the third region LA in the high gradation higher than the intermediate gradation, thereby allowing the light and the color filter to pass through the color filter 230. The light of the third region LA from which the 230 is removed is displayed, thereby increasing luminance. Therefore, it is possible to increase the color reproducibility in low gradation while increasing the luminance in high gradation.

Next, a liquid crystal display according to another exemplary embodiment of the present invention will be described with reference to FIGS. 8 to 10. FIG. 8 is an equivalent circuit diagram showing one pixel together with the structure of a liquid crystal display according to another embodiment of the present invention, FIG. 9 is a layout view of a liquid crystal display according to another embodiment of the present invention, and FIG. 9 is a cross-sectional view of the liquid crystal display of FIG. 9 taken along the line IX-IX.

As shown in FIG. 8, the liquid crystal display according to the exemplary embodiment includes a lower panel 100 and an upper panel 200 facing each other and a liquid crystal layer 3 interposed therebetween.

The liquid crystal capacitors Clca and Clcb have two terminals, the subpixel electrodes PEa / PEb of the lower panel 100 and the common electrode CE of the upper panel 200, and the subpixel electrodes PEa / PEb and the common electrode. The liquid crystal layer 3 between 270 functions as a dielectric. The pair of subpixel electrodes PEa / PEb are separated from each other and form one pixel electrode PE. The common electrode CE is formed on the front surface of the upper panel 200 and receives a common voltage. The liquid crystal layer 3 has negative dielectric anisotropy, and the liquid crystal molecules of the liquid crystal layer 3 may be aligned such that their major axes are perpendicular to the surfaces of the two display panels in the absence of an electric field.

Meanwhile, in order to implement color display, each pixel uniquely displays at least two of a primary color such as three primary colors such as red, green, and blue, and white or yellow, and a region occupied by the first pixel electrode PEa and a second pixel Some of the area occupied by the electrode PEb may display one of the primary colors, and the remaining area occupied by the second pixel electrode PEb may be white or yellow.

Polarizers (not shown) are provided on the outer surfaces of the display panels 100 and 200, and polarization axes of the two polarizers may be orthogonal to each other. In the case of a reflective liquid crystal display, one of two polarizers may be omitted. In the case of the orthogonal polarizer, incident light entering the liquid crystal layer 3 having no electric field is blocked.

9 and 10, a specific example of the liquid crystal display shown in FIG. 8 will be described in detail.

First, the lower panel 100 will be described.

A plurality of gate conductors including a plurality of gate lines 121a and 121b and a capacitor voltage line 131 are formed on the insulating substrate 110. The first gate line 121a includes a first gate electrode 124a and a second gate electrode 124b, and the second gate line 121b includes a third gate electrode 124c.

The capacitor voltage line 131 transmits a constant capacitance voltage and is disposed on an upper portion of the pixel to form a stem line extending substantially parallel to the gate lines 121a and 121b and a plurality of branches extending therefrom. Include. Each branch line includes a vertical portion 134, a horizontal portion 135, and a capacitor electrode 137, and the stem line includes a storage electrode 133 having a large area up and down. The vertical portion 134 extends straight down from the stem line, and the horizontal portion 135 vertically meets the vertical portion 134. The capacitor electrode 137 protrudes downward from the horizontal part 135 from the center of the horizontal part 135 to the right vertical part 134. The shape and arrangement of the capacitor voltage line 131 may be modified in various forms.

The gate insulating layer 140 is formed on the gate conductors 121a, 121b, and 131.

The linear semiconductor 151 is formed on the gate insulating layer 140. The linear semiconductor 151 mainly includes a stem portion extending in the vertical direction and a plurality of first branch portions 154a extending toward the first gate electrode 124a, the second gate electrode 124b, and the third gate electrode 124c. ), A second branch portion 154b and a third branch portion 154c. The plurality of first branch portions 154a, the second branch portions 154b, and the third branch portions 154c respectively include the first gate electrode 124a, the second gate electrode 124b, and the third gate electrode 124c. First to third element portions (not shown) are disposed above. The third branch portion 154c extends to form the fourth branch portion 157.

On the semiconductors 154a, 154b, 154c, and 157, a linear ohmic contact 161 including a protrusion 164b, a first island-type ohmic contact (not shown), a second island-type ohmic contact (not shown), and A third island type ohmic contact member (not shown) and a fourth island type ohmic contact member 167 are formed. The linear ohmic contact is arranged over the first protrusion of the semiconductor in pairs with the first island resistive contact member and is disposed over the second protrusion of the semiconductor in pairs with the second island of ohmic contact. And a third protrusion (not shown) disposed over the third protrusion of the semiconductor in pairs with a second protrusion (not shown) and a third island-type resistive contact member.

On the ohmic contacts 161 and 167 and the gate insulating layer 140, a plurality of data lines 171, a plurality of first drain electrodes 175a, a second drain electrode 175b, and a third source electrode 173c, and The data conductor including the third drain electrode 175c is formed.

The data line 171 includes a plurality of first source electrodes 173a and second source electrodes 173b.

The first to third drain electrodes 175a, 175b, and 175c include the first to third extensions 177a, 177b, and 177c, which are wide ends, and the other ends that are rod-shaped. The rod-shaped end portions of the first drain electrode 175a, the second drain electrode 175b, and the third drain electrode 175c may include the first source electrode 173a, the second source electrode 173b, and the third source electrode. It is partially surrounded by (173c). The third source electrode 173c is connected to the second extension 177b of the second drain electrode 175b.

The semiconductors 154a, 154b, 154c, and 157 are substantially the same plane as the data line 171, the first to third electrode members 175a, 175b, and 175c, and the ohmic contacts 163a, 165a, and 167c thereunder. It is a shape. However, the linear semiconductor is exposed between the source electrodes 173a, 173b, and 173c and the drain electrodes 175a, 175b, and 175c, and is not covered by the data line 171 and the drain electrodes 175a, 175b, and 175c.

The lower passivation layer 180p is formed on the data conductors 171, 175a, 175b, and 175c and the exposed semiconductors 154a, 154b, and 154c.

The lower passivation layer 180p may be made of an inorganic insulator such as silicon nitride or silicon oxide, and may prevent the components of the color filter 230 formed thereon from being diffused into the underlying thin film transistor.

A light blocking member 220 is formed on the lower passivation layer 180p. The light blocking member 220 is also called a black matrix and prevents light leakage. In the illustrated embodiment, the light blocking member 220 is formed on the lower panel 100, but in another embodiment, the light blocking member 220 may be formed on the upper panel 200.

A plurality of color filters 230 are formed on the lower passivation layer 180p and the light blocking member 220. The color filter 230 may display one of primary colors such as three primary colors of red, green, and blue, and may be formed of an organic material including a pigment displaying one of the three primary colors.

The color filter 230 extends up and down from an area where the two gate lines 121a and 121b are positioned, and is removed from some of the lower areas of the pixel.

In the illustrated embodiment, the color filter 230 is formed on the lower panel 100, but in another embodiment, the color filter 230 may be formed on the upper panel 200.

An upper passivation layer 180q is formed on the lower passivation layer 180p and the plurality of color filters 230. The upper passivation layer 180q may be formed of an organic insulating layer, and may be formed of an organic material having photosensitivity. The upper passivation layer 180q prevents the color filter 230 from floating and suppresses contamination of the liquid crystal layer 3 by organic substances such as a solvent flowing from the color filter 230, resulting in afterimages that may occur when driving the screen. To prevent such defects.

In the upper passivation layer 180q and the lower passivation layer 180p, a plurality of contact holes exposing the first extension 177a of the first drain electrode 175a and the second extension 177b of the second drain electrode 175b ( 185a and 185b are formed, and a plurality of contact holes 185c exposing a portion of the capacitor electrode 137 are formed in the upper passivation layer 180q, the lower passivation layer 180p, and the gate insulating layer 140.

A plurality of pixel electrodes 191 are formed on the upper passivation layer 180q. Each pixel electrode 191 is separated from each other with the two gate lines 121a and 121b interposed therebetween, and is disposed above and below the pixel area around the gate lines 121a and 121b and adjacent to each other in the column direction. 191a and the second pixel electrode 191b. The overall shape of each of the subpixel electrodes 191a and 191b is quadrangular and includes a cross stem portion including a horizontal stem portion and a vertical stem portion orthogonal thereto. Each subpixel electrode 191a, 191b is divided into four subregions by a stem, and each subregion includes a minute branch portion. The minute branches may form an angle of about 45 degrees or 135 degrees with the stem, and the minute branches of two neighboring subregions may be perpendicular to each other.

The first pixel electrode 191a and the second pixel electrode 191b are respectively connected to the first drain electrode 175a or the second drain electrode 175b through the first contact hole 185a and the second contact hole 185b. It is connected and receives a data voltage from the first drain electrode 175a and the second drain electrode 175b. The first pixel electrode 191a and the second pixel electrode 191b to which the data voltage is applied generate a electric field together with the common electrode 270 of the common electrode display panel 200, thereby forming a liquid crystal layer between the two electrodes 191 and 270. The direction of the liquid crystal molecules of (3) is determined. The luminance of light passing through the liquid crystal layer 3 varies according to the direction of the liquid crystal molecules determined as described above. At this time, the sides of the minute branches distort the electric field to produce a horizontal component that determines the inclination direction of the liquid crystal molecules 31. The horizontal component of the electric field is almost horizontal to the sides of the fine branch. Therefore, the direction in which the liquid crystal molecules 31 are inclined is approximately four directions, and four domains having different alignment directions of the liquid crystal molecules 31 are formed in the liquid crystal layer 3. As described above, when the liquid crystal molecules are inclined in various directions, the reference viewing angle of the liquid crystal display is increased.

The second pixel electrode 191b is physically and electrically connected to the third source electrode 173c through the contact hole 185b.

The expansion portion 177c of the capacitor electrode 137 and the third drain electrode 175c overlaps each other with the gate insulating layer 140 and the semiconductor layers 157 and 167 interposed therebetween to form a reduced pressure capacitor.

A lower alignment layer (not shown) is formed on the pixel electrode 191 and the exposed upper passivation layer 180q. The lower alignment layer may be a vertical alignment layer.

The upper panel 200 will now be described.

The common electrode 270 is formed on the insulating substrate 210. An upper alignment layer (not shown) is formed on the common electrode 270. The upper alignment layer may be a vertical alignment layer.

The liquid crystal layer 3 has negative dielectric anisotropy, and the liquid crystal molecules of the liquid crystal layer 3 are aligned such that their major axes are perpendicular to the surfaces of the two display panels 100 and 200 in the absence of an electric field.

When a gate-on voltage is applied to the first gate line 121a, the data line is applied to the first pixel electrode 191a and the second pixel electrode 191b through the first drain electrode 175a and the second drain electrode 175b. The data voltage applied to 171 is applied. In this case, the data voltages applied to the first pixel electrode 191a and the second pixel electrode 191b are the same. The first and second liquid crystal capacitors Clca and Clcb are charged to the same value by the difference between the common voltage and the data voltage.

Thereafter, the voltage applied to the first gate signal line 121a is changed from the gate on voltage to the gate off voltage, and at the same time, the voltage applied to the second gate line 121b is changed from the gate off voltage to the gate on voltage. The charge is transferred from the pixel electrode 191b through the third source electrode 173c to the third drain electrode 175c. Thereby, the charging voltage of a 2nd liquid crystal capacitor becomes low and a pressure reduction capacitor is charged. Since the charging voltage of the second liquid crystal capacitor Clcb is lowered by the capacitance of the decompression capacitor, the charging voltage of the second liquid crystal capacitor Clcb is lower than the charging voltage of the first liquid crystal capacitor Clca.

At this time, the charging voltages of the two liquid crystal capacitors Clca and Clca show different gamma curves, and the gamma curve of one pixel voltage becomes a curve obtained by synthesizing them. The composite gamma curve at the front side is matched to the reference gamma curve at the front that is best suited, and the composite gamma curve at the side is closest to the reference gamma curve at the front. In this way, side visibility is improved by converting the video data.

In addition, the electric field applied to one pixel PX of the liquid crystal display according to the present embodiment has a different intensity from the electric field applied to the liquid crystal layer 3, specifically, the electric field applied to the liquid crystal layer 3 has a relatively high intensity. The area occupied by the large first pixel electrode 191a and the electric field applied to the liquid crystal layer 3 are divided into regions occupied by the second pixel electrode 191b having a relatively small intensity, and the color filter 230 is a liquid crystal layer 3. Only a portion of the region having a large electric field intensity, the region occupied by the first pixel electrode 191a, the region having a small intensity of the electric field applied to the liquid crystal layer 3, and the region occupied by the second pixel electrode 191b. The second pixel electrode 191b may be disposed and removed from the rest of the area occupied by the second pixel electrode 191b. At this time, the area of the area occupied by the second pixel electrode 191b without the color filter is preferably less than 1/2 of the area occupied by the second pixel electrode 191b with the color filter. In addition, the area of the area where the color filter 230 is removed among the areas occupied by the second pixel electrode 191b is preferably within 20% of the area of the pixel area.

As such, by dividing one pixel area into two regions having different electric field intensities applied to the liquid crystal layer 3, and removing the color filter 230 in a part of the region having small electric field intensity applied to the liquid crystal layer 3, The color reproducibility is increased at low gradations, and the luminance is increased at high gradations above intermediate gradations. Therefore, it is possible to increase the color reproducibility in low gradation while increasing the luminance in high gradation.

Many features of the liquid crystal display according to the above-described embodiment are also applicable to the liquid crystal display according to the present embodiment.

Next, another example of the liquid crystal display illustrated in FIG. 8 will be described with reference to FIGS. 11 and 12 along with FIG. 8. FIG. 11 is a layout view of a liquid crystal display according to another exemplary embodiment. FIG. 12 is a cross-sectional view of the liquid crystal display shown in FIG. 11 taken along the line XII-XII.

11 and 12, a liquid crystal display according to another exemplary embodiment includes a lower panel 100 and an upper panel 200 facing each other and a liquid crystal layer 3 interposed therebetween. .

First, the lower panel 100 will be described.

A plurality of pairs of first and second gate lines 121a and 121b and a storage electrode line 131 are formed on the substrate 110. Each of the first and second gate lines 121a and 121b includes a plurality of first and second gate electrodes 124a and 124b.

A gate insulating layer 140 is formed on the gate lines 121a and 121b and the storage electrode line 131, and a plurality of island-like semiconductors 154a and 154b are formed on the gate insulating layer 140, and the semiconductors 154a and 154b are formed. A plurality of island type ohmic contact members 163a and 165a are formed thereon.

A plurality of pairs of data lines 171 and 172 and a plurality of pairs of first and second drain electrodes 175a and 175b are formed on the gate insulating layer 140 and the ohmic contacts 163a and 165a. The data lines 171 and 172 are not in a straight line throughout and are bent at least twice per pixel. In detail, as illustrated in FIG. 4, the data lines 171 and 172 are bent to the right from the first vertical portions 171a and 172a and the first vertical portions 171a and 172a extending in the vertical direction, and then the first horizontal lines extend in the horizontal direction. After bending down from the horizontal portions 171c and 172c, the first horizontal portions 171c and 172c, the second vertical portions 171b and 172b extending in the vertical direction and the second vertical portions 171b and 172b are folded to the left. And second horizontal portions 171d and 172d extending laterally. Each of the first vertical portions 171a and 172a and the second vertical portions 171b and 172b of the two data lines 171 and 172 is disposed on an imaginary straight line parallel to each other and spaced apart from each other. The data line 171 includes a plurality of first and second source electrodes 173a and 173b extending toward the gate electrodes 124a and 124b.

A passivation layer 180 is formed on the data lines 171 and 172, the drain electrodes 175a and 175b, and the exposed portions of the semiconductors 154a and 154b. The passivation layer 180 includes a lower layer 180p made of an inorganic insulator such as silicon nitride or silicon oxide and an upper layer 180q made of an organic insulator. The organic insulator preferably has a dielectric constant of 4.0 or less, may have photosensitivity, and may provide a flat surface. The passivation layer 180 may have a single layer structure made of an inorganic insulator or an organic insulator. The upper layer 180q of the passivation layer 180 may be formed to a thickness of 1.0 μm or more in order to reduce the coupling phenomenon between the pixel electrode 191 and the data lines 171 and 172 and to planarize the substrate.

The passivation layer 180 is provided with a plurality of contact holes 185a and 185b exposing the first and second drain electrodes 175a and 175b, respectively.

A plurality of pixel electrodes 191 including the first and second subpixel electrodes 191a and 191b are formed on the passivation layer 180.

The first and second subpixel electrodes 191a and 191b are physically and electrically connected to the first and second drain electrodes 175a and 175b through the contact holes 185a and 185b to form the first and second drain electrodes ( Data voltage is applied from 175a / 175b). Different data voltages, which are set in advance with respect to one input image signal, are applied to the pair of subpixel electrodes 191a and 191b, the size of which is set according to the size and shape of the subpixel electrodes 191a and 191b. Can be. The areas of the subpixel electrodes 191a and 191b may be different from each other. For example, the first pixel electrode 191a receives a higher voltage than the second pixel electrode 191b and has a smaller area than the second pixel electrode 191b.

Meanwhile, horizontal boundaries between the first pixel electrode 191a and the second vertical line 171a of the data line 171 of the data line 171, which are bent out of the pixel electrode 191, respectively, are adjacent to each other. It is formed adjacent to the vertical part 172b, and is spaced at predetermined intervals. That is, when the first subpixel electrode is projected onto the same plane as the first data line and the second data line, their projection patterns are spaced apart from each other. Therefore, the first pixel electrode 191a does not overlap with the data lines 171 and 172, but is spaced apart from the data lines 171 and 172, so that the first pixel electrode 191a and the data lines 171 and 172 are separated from each other. By reducing the coupling phenomenon, cross talk failure caused by the coupling of the first pixel electrode 191a and the data lines 171 and 172 is prevented.

The second pixel electrode 191b overlaps the portion 171b of the data line 171 and overlaps the portion 172a of the data line 172 neighboring the data line 171. As such, the second pixel electrode 191b may be formed to overlap the portion 171b of the data line 171 and the portion 172a of the neighboring data line 172 to increase the aperture ratio of the liquid crystal display. In this case, an area where the second pixel electrode 191b overlaps the data line 171 and the drain electrode 175b and an area where the second pixel electrode 191b overlaps the portion 172a of the neighboring data line 172 Is about 0.8: 1 to about 1.2: 1. As such, the second pixel electrode 191b respectively adjusts the area ratio of the left and right neighboring data lines 171 and 172 so that the second pixel electrode 191b respectively neighbors the left and right data lines 171. , 172 and the difference in parasitic capacitances to be formed can be reduced to prevent crosstalk failure caused by parasitic capacitance variation between the second pixel electrode 191b and the neighboring data lines 171 and 172.

Next, the upper panel 200 will be described.

The light blocking member 220, the color filter 230, the overcoat 250, and the common electrode 270 are sequentially formed on the insulating substrate 210.

In the illustrated embodiment, the light blocking member 220 and the color filter 230 are formed on the upper panel 200, but in another embodiment, the light blocking member 220 and the color filter 230 are formed on the lower panel 100. May be

The color filter 230 is disposed in a portion of the region occupied by the first pixel electrode 191a and the region occupied by the second pixel electrode 191b, and is removed from the remaining region of the region occupied by the second pixel electrode 191b. have. At this time, the area of the area occupied by the second pixel electrode 191b without the color filter is preferably less than 1/2 of the area occupied by the second pixel electrode 191b with the color filter. In addition, the area of the area where the color filter 230 is removed among the areas occupied by the second pixel electrode 191b is preferably within 20% of the area of the pixel area.

As such, by dividing one pixel area into two regions having different electric field intensities applied to the liquid crystal layer 3, and removing the color filter 230 in a part of the region having small electric field intensity applied to the liquid crystal layer 3, The color reproducibility is increased at low gradations, and the luminance is increased at high gradations above intermediate gradations. Therefore, it is possible to increase the color reproducibility in low gradation while increasing the luminance in high gradation.

An alignment layer (not shown) is coated on the inner surfaces of the display panels 100 and 200 and may be a vertical alignment layer.

Polarizers (not shown) are provided on the outer surfaces of the display panels 100 and 200, and the transmission axes of the two polarizers are orthogonal to each other, and one of the transmission axes is parallel to the gate line 121.

The liquid crystal layer 3 has negative dielectric anisotropy, and the liquid crystal molecules of the liquid crystal layer 3 are aligned such that their major axes are perpendicular to the surfaces of the two display panels 100 and 200 in the absence of an electric field. Therefore, incident light does not pass through the orthogonal polarizer and is blocked.

The cutouts 92a, 92b, 93a, and 93b of the pixel electrode and the cutouts 71 to 74b of the common electrode and the hypotenuse of the pixel electrode 191 parallel thereto are disposed between the pixel electrode 191 and the common electrode 270. It distorts the electric field applied to it, creating a horizontal component that determines the tilt direction of the liquid crystal molecules. The horizontal component of the electric field is perpendicular to the hypotenuse of the cutouts 92a-93b, 92b, 71-74b and the hypotenuse of the pixel electrode 191. As described above, when the liquid crystal molecules are inclined in various directions, the reference viewing angle of the liquid crystal display is increased.

The at least one cutout 92a to 93b and 71-74b may be replaced with a protrusion or a depression, and the shape and arrangement of the cutouts 92a to 93b and 71-74b may be modified.

Many features of the liquid crystal display according to the above-described embodiment are also applicable to the liquid crystal display according to the present embodiment.

Next, a transmittance of the liquid crystal display according to an exemplary embodiment of the present invention will be described with reference to FIG. 13. 13 is a graph showing a voltage-transmittance curve according to an experimental example of the present invention.

In the present experimental example, as in the embodiment shown in FIG. 6, one pixel PX region is divided into three regions HA, MA, and LA having different intensities of electric fields applied to the liquid crystal layer 3. The ratio of the area of the first area HA, the area of the second area MA, and the area of the third area LA is about 1: 3: 1, and the voltage-transmittance curve in each area The voltage-transmission curves in all the pixels are shown in FIG. 12.

Referring to FIG. 13, referring to the voltage-transmittance curve c of the third region LA, the transmittance is very small at low voltage, and the transmittance increases greatly from the middle voltage or more. In addition, referring to the voltage-transmittance curve (a) of the first region HA and the voltage-transmission curve (b) of the second region MA, it can be seen that the transmittance is high even at a low voltage. Therefore, as shown in the voltage-transmittance curve s of the entire pixel region, it was found that the luminance in the high gradations can be increased while the color reproducibility in the low gradations is increased.

Specifically, as in the embodiment of the present invention, the color filter is formed only in the first region HA and the second region MA, in which the electric field applied to the liquid crystal layer 3 has a relatively high intensity, and the liquid crystal layer 3 By removing the color filter in the third area LA where the electric field is relatively small in intensity, in low gradation, the light passing through the color filter under the influence of the first area HA and the second area MA is removed. The higher the transmittance, the higher the color reproducibility, and the higher the gray scale or higher, the higher the transmittance in the first region HA, the second region MA, and the third region LA, and especially the third region in which the color filter is removed. Since the transmittance of LA) is high, the overall luminance is high. Therefore, it was possible to increase the luminance in high gradations while increasing the color reproducibility in low gradations.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (31)

A first substrate and a second substrate facing each other,
A plurality of signal lines arranged on the first substrate, and
A first pixel electrode and a second pixel electrode connected to the plurality of signal lines and separated from each other;
The first pixel electrode and the second pixel electrode include a plurality of branch electrodes, wherein the branch electrode of the first pixel electrode and the branch electrode of the second pixel electrode are alternately disposed.
The first pixel electrode and the second pixel electrode may include a first region having a first distance between a branch electrode of the neighboring first pixel electrode and a branch electrode of the second pixel electrode, and the neighboring first pixel electrode. A second region wherein a distance between the branch electrode of and the branch electrode of the second pixel electrode is a second distance less than the first distance, and
A portion of the first region and the second region display a first color, and the other portion of the first region displays a second color. In claim 1,
The first color is any one of the primary colors, and the second color is white or yellow. In claim 2,
A color filter is disposed in an area displaying the first color, and a color filter is removed in an area displaying the second color. 4. The method of claim 3,
And the color filter is disposed on the first substrate. In claim 4,
The color filter is disposed between the signal line and the pixel electrode.
And a transparent organic insulating layer disposed in the region displaying the second color. 4. The method of claim 3,
And the color filter is disposed on the second substrate. 4. The method of claim 3,
And an area displaying the second color is within 20% of a total area occupied by the first pixel electrode and the second pixel electrode. 4. The method of claim 3,
An area of the area of the first area displaying the second color is less than or equal to 1/2 of an area of the area of the first area displaying the first color. In claim 1,
And an area displaying the second color is within 20% of a total area occupied by the first pixel electrode and the second pixel electrode. In claim 1,
An area of the area of the first area displaying the second color is less than or equal to 1/2 of an area of the area of the first area displaying the first color. In claim 1,
Further comprising a liquid crystal layer disposed between the first substrate and the second substrate,
And a long axis of the liquid crystal molecules of the liquid crystal layer perpendicular to a surface of the first substrate and the second substrate in the absence of an electric field. In claim 1,
The first region further includes a third region in which a distance between a branch electrode of the first pixel electrode and a branch electrode of the second pixel electrode, which are adjacent to each other, is a third distance greater than the first distance,
The liquid crystal display of the first area is a region that displays the second color. In claim 12,
An area of the third region is equal to or smaller than an area of the second region,
The area of the first area in which the distance between the branch electrodes of the first pixel electrode and the branch electrode of the second pixel electrode is the first distance among the first areas is three times or more than the area of the third area. Device. In claim 13,
The first color is any one of the primary colors, and the second color is white or yellow. The method of claim 14,
A color filter is disposed in an area displaying the first color, and a color filter is removed in an area displaying the second color. The method of claim 15,
And the color filter is disposed on the first substrate. The method of claim 16,
The color filter is disposed between the signal line and the pixel electrode.
And a transparent organic insulating layer disposed in the region displaying the second color.
The method of claim 15,
And the color filter is disposed on the second substrate. In claim 12,
The area of the third region is less than 20% of the total area occupied by the first pixel electrode and the second pixel electrode. In claim 12,
Further comprising a liquid crystal layer disposed between the first substrate and the second substrate,
And a long axis of the liquid crystal molecules of the liquid crystal layer perpendicular to a surface of the first substrate and the second substrate in the absence of an electric field. First and second substrates facing each other
A plurality of signal lines arranged on the first substrate,
A pixel electrode connected to the plurality of signal lines and including a first subpixel electrode and a second subpixel electrode separated from each other, and
A liquid crystal layer interposed between the first substrate and the second substrate and including liquid crystal molecules;
The voltage charged in the liquid crystal layer disposed in the region occupied by the first subpixel electrode is lower than the voltage charged in the liquid crystal layer disposed in the region occupied by the second subpixel electrode.
And a region occupied by the portion of the first subpixel electrode and the second subpixel electrode displays a first color, and a region occupied by the remaining portion of the first subpixel electrode displays a second color.
22. The method of claim 21,
The first color is any one of the primary colors, and the second color is white or yellow. The method of claim 22,
A color filter is disposed in an area displaying the first color, and a color filter is removed in an area displaying the second color. The method of claim 23,
And the color filter is disposed on the first substrate. 25. The method of claim 24,
The color filter is disposed between the signal line and the pixel electrode.
And a transparent organic insulating layer disposed in the region displaying the second color. The method of claim 23,
And the color filter is disposed on the second substrate. The method of claim 23,
And an area displaying the second color is within 20% of a total area occupied by the first pixel electrode and the second pixel electrode. The method of claim 23,
And an area of the area displaying the second color among the areas occupied by the first pixel electrode is less than 1/2 of an area of the area displaying the first color among the areas occupied by the first pixel electrode. 22. The method of claim 21,
And an area displaying the second color is within 20% of a total area occupied by the first pixel electrode and the second pixel electrode. 22. The method of claim 21,
And an area of the area displaying the second color among the areas occupied by the first pixel electrode is less than 1/2 of an area of the area displaying the first color among the areas occupied by the first pixel electrode. 22. The method of claim 21,
And a long axis of the liquid crystal molecules of the liquid crystal layer perpendicular to a surface of the first substrate and the second substrate in the absence of an electric field.

Images